U.S. Pat. No. 5,711,790 and U.S. Pat. No. 5,735,940 (Coller) disclose water-based marking compositions which can be removed from a substrate surface. Such compositions comprise water, water-soluble salt or mixtures of water-soluble salts, and colorant(s), and are used for producing colored temporary marks on surfaces, especially snow or ice. However, these markings do not spontaneously disappear from the surface. To be removed, they have to be washed off, for example, by rain or disappear with snow or ice as they melt.
U.S. Pat. No. 6,077,898 (Flores) refers to aqueous aerosol paint compositions comprising a film-forming polymer suitable for temporarily marking tunnels and roads. Like the markings produced by the compositions of U.S. Pat. No. 5,711,790 and U.S. Pat. No. 5,735,940, these markings are also temporary, but they do not disappear by themselves and should be removed with water, for example by rain.
U.S. Pat. No. 5,174,571 (Aubusson, et al.) discloses a method and apparatus for forming temporary visible lines on a surface using laser beams. They are primarily intended for forming the demarcation lines of courts and fields of a number of different sports in a multi-purpose area but in which only the demarcation lines for any one particular sport are visible at any one time.
Documents NL 8801010 e NL 8800622 (Nijenhuis) relates to a system of illuminated markers consisting of bundles of fibre optic cables disposed under a playing area linked to a light generating equipment. Such a system is intended for forming the demarcation lines of courts and fields so that the same place can be used for different games.